Publisher : The Korean Society of Mechanical Engineers
DOI : 10.22634/KSME-B.19126.96.36.1996
Title & Authors
Experimental study of turbulent flow in a U-bend of circular cross-section Lee, Geon-Hwi;
Hot-wire measurement of the longitudinal and radial velocity components and Reynolds stresses are reported for developing turbulent flow in a strongly curved 180 deg. pipe and its tangents. Slanted wire is rotated to 6 directions and the voltage outputs of them are combined to obtain the mean velocities and Reynolds stresses. Significant double maxima in the longitudinal velocity component appear in the bend. V-profiles reveal the development of a strong secondary flow. This secondary flow is induced by the transverse pressure gradient set up between the outer(ro/) and inner(ri/) wall region of the bend. Another second cross-stream flow develops after .theta.=135 deg. and its direction is opposed to that of main second flow.